(1) Field of the Invention
This invention relates generally to humidifier devices and more particularly to disposable humidifier cartridges assemblies which receive water from an adjacent container.
(2) Prior Art
Inhalation therapy generally includes a humidifying means where oxygen, air, other gases which ought to be breathed by a patient, to aid in his respiration, are preferably both heated and humidified under controlled conditions. It is preferred that a sterile liquid be used for the humidification process.
Such inhalation therapy equipment is shown for instance in U.S. Pat. No. 4,110,419, wherein a heated cartridge receives a supply of water from a vented, rigid walled container.
U.S. Pat. No. 4,366,105 shows a humidifier system with a water source feeding a cartridge type heater-humidifier, having a plurality of clamps and check-valves. The clamps must be manually operated and the level of water checked periodically. A further example of the art is shown in U.S. Pat. No. 4,500,480 which shows a pediatric cartridge humidifier having a plurality of conduits disposed between the humidifier and the water supply. The prior art does not permit the cartridge heaters to have automatic shut-off control which is a very desirable feature to minimize the extent of maintenance of such an inhalation system, and to guard against the possiblity of over-flow of the system to the detriment (possible drowning) of the patient. This is of critical significance when the system is in use in a pediatric environment. Baxter Travenol makes an "Optimal" column which uses a pair of manually regulatable conduits from a rigid walled water source, one conduit for supply and the other conduit for venting, in addition to a port to the patient and a port from the gas source.
It is an object of the present invention to provide an inhalation system which is fail-safe in operation. That is, where shut-off is positive and automatic, not needing manual control, which guards against the flooding of the system.
It is yet a further object of the present invention to provide an inhalation system where the water level is constant, a situation, particularly desirable in pediatric use.